Laying-down system and vision-based automatic primal cutting system in connection therewith

ABSTRACT

In the primal cutting-up of half carcasses of animals ( 12 ), vision systems are known whereby the determination of one or more fix points on the carcasses takes place, and where on the basis of the position of these points a visualisation of the ideal cut line is effected. But the primal cutting-up of carcasses ( 12 ) has hitherto been carried out with manually-operated saws on the basis of operator evaluation. However, the use of manually-operated saws involves the possibility of deviations in relation to the ideal cut line, and the manual work is very monotonous and fatiguing for the operators. 
     There is thus disclosed a laying-down module ( 2 ) and a vision-based system for automatic primal cutting-up of half carcasses, comprising a laying-down module with a laying-down conveyor ( 18 ), and a laying-down and angle-positioning module ( 6 ) with sideways displaceable conveyors for positioning of a relevant carcass ( 12 ) for sawing-up in a subsequent saw module ( 8 ), and a method for the execution of automatic primal cutting-up of meat items, namely half carcasses of animals.

The present invention concerns a laying-down system for buildingtogether with a plant for the primal cutting-up of meat items, namelyhalf carcasses of pigs. The invention also concerns a fully-automaticsystem for the primal cutting-up of meat items, namely half carcasses ofpigs, and comprising a laying-down module, a vision-based detectionsystem for the determination of relevant fix points on meat items, acalculation unit with interface for the controlling of a positioningmodule and a sawing module. Moreover, the invention concerns a methodbased on a vision system for primal cutting-up of meat items.

The dividing-up of half pig carcasses is traditionally carried out by anoperator placed at a conveyor belt on which the carcasses pass, in thathe manually corrects (pulls/pushes) the half carcass in position for asaw (circular knife) which is disposed above the conveyor belt. Withthis method, use is made of an operator and a saw for each cut which ismade in the half carcasses.

The way in which the correction of the half carcasses is typicallycarried out is that a line laser marker mounted on the individual sawsirradiates the conveyor band immediately in front of the saw in animaginary line through the blade of the saw, and the operator uses thislaser beam in moving the half carcass manually so that this is sawnthrough in the desired place.

The above-mentioned method has several disadvantages. In the firstplace, the operator's work is monotonous and physically demanding, andoperators who carry out this work are worn-out by the work after arelatively short period. Secondly, the positioning of the cut is basedon the subjective judgement of the individual operator, so that theaccuracy can fall with changing operators, inattention on the part ofthe operator, or if he has difficulty in maintaining the necessaryconcentration over longer periods of time. Thirdly, the definition ofthe correct knife positioning can change during the course of theproduction, which necessitates verbal communication of the changedrequirements out to a number of operators, which involves possibilitiesof error.

Efforts have been made to automate the above-mentioned method, forexample in DK B 161 656 there is disclosed a semi-automatic plant of thekind whereby an operator moves a position-provider coupled to a laserbeam to the positions on the half carcass where he judges that the cutsshall be placed. When the laser beam irradiates the place of the cut,the operator activates an operating element, whereby the position of theposition-provider is read into a control system. The positions of thecutting places are used to position the half carcasses and thesubsequent saws, so that the different cuts are effected in accordancewith the judgement of the operator. The publication also discloses amethod for arranging the individual half carcasses so that theirlengthways axes are positioned at right-angles to the feeding direction.With the said system, it is thus possible for human errors of judgementto be made in connection with the positioning which determines the cutswhich are to be carried out in the half carcasses.

In DK T3 0 594 528, a system is disclosed by which, with the help ofmechanical measuring of the half carcasses, it can carry out atripartition of these (ham and fore-end cuts). The arranging of the halfcarcasses to the correct angle takes place in connection with themeasuring of fix points in the pig carcass, in that this is drawn overthe surface of the conveyor by means of the mechanical measuring means.

The above-mentioned methods are based either on manual or mechanicallocalisation of the fix points which form the starting point for thecutting-up positions.

DK B1 167 462 discloses a vision system for the determination of saidfix points on the half of an animal carcass, said vision system beingcoupled to a computer for the implementation of picture analysis which,after the determination of the position of fix points in a manner whichis not specified, is said to send control signals to mechanisms whichare not further described, and which on the basis of the positioning ofthe fix points carry out the arranging of the carcass and of thesystem's tools for the cutting-up of said carcass.

However, several different patents and patent applications are to befound which deal with actual vision analyses of meat products, partlywith the view of classifying meat products, e.g. for determining themarket value, and partly to be able to determine the position of certainstructures. Among these there are two German publications, DE C2 41 31556 and DE A1 41 09 345, to which reference is made when, in connectionwith the present invention application, vision analysis/determination offix points on half carcasses is discussed. The precondition for thepresent invention is thus that the position of the fix points on halfcarcasses, which are used as starting point for the determination of theindividual cuts, takes place by means of said vision system. The visionsystem comprises a video camera which takes a picture of the halfcarcass while this passes under the camera on a conveyor. The camera iscoupled to a computer, which with specially-developed softwarerecognises the contours and inner structure of the half carcass, such ase.g. vertebrae in the spine and the pubis. Hereafter, with greataccuracy the computer calculates the positions of the individual fixpoints in relation to a given zero line. By means of the computertogether with suitable interface and actuators, the positioning of thefix points in relation to the zero line can subsequently be used foreffecting mutual positioning of the half carcasses/saws with startingpoint in a beforehand desired positioning of the cuts in relation tosaid positioning of said fix points. The positioning can take placeeither by effecting a displacement of the saws (saw blades) in thelateral direction, still with the blades arranged parallel with thetransport direction, and/or by using conveyor plant which can bedisplaced in the transverse direction by means of actuators.

The above-mentioned method and system is particularly suitable for usewhen an ordinary “industrial cut” is to be made (double cut where thefore-end and hams are separated from the central piece) at right-anglesto the length-ways direction of the carcass, where the half carcassesare transported with the lengthways direction arranged at right-anglesto the direction of transport, and where the parting cuts are placed inrelation to the positions of the fix points by positioning of the halfcarcasses on sideways-displaceable conveyors, and positioning of thesaws in the sideways direction.

If only a ham cut is to be carried out, which is sometimes known as a“Belgian cut”, also in the following, it will not be possible to use theabove-mentioned method for automatic parting of the carcass, in that aBelgian cut is effected as an inclined cut in relation to the lengthwaysdirection of the carcass, though still in relation to the positioning ofthe relevant fix point on the half carcass. When carrying out theparting with this type of cut, it has thus hitherto been necessary toeffect the cutting manually with manually-operated saws with lasermarking of the positioning of the cut, in that the cut which is carriedout here shall extend at an angle in relation to the direction oftransport. Neither is the above-mentioned method particularly suitablewhen it is preferred to carry out an optimised industrial cut, whichoften involves the placing of the cuts at an angle which deviates fromright-angles to the lengthways direction of the carcass.

For solving the above-mentioned problems in connection with the placingof the meat items, there is thus disclosed a laying-down module of thekind which is disclosed and characterised in claim 1.

With the U-shaped laying-down fixtures, it is hereby achieved that themeat item/half carcass, after receipt by being successively fed forwardsby the suspension conveyor, is placed in the low points of the fixtures,so that before the laying-down on the laying-down conveyor, these arearranged so that the half carcass in the under-supporting points definedby the low points of the two outermost fixtures is lying in a line whichis arranged substantially at right-angles to the transport direction ofthe laying-down conveyor. There is hereby achieved a very uniformpositioning and orientation of the transported carcasses, which by thevertical downwards-directed displacement of the fixtures subsequentlyplaces the half carcasses in this position on the laying-down conveyorfor transport in the further cutting-up process. Moreover, it will notalways be certain that the low point in the centremost fixture lies onthe line which can be drawn between the two outermost fixtures.

Moreover, with this construction of the laying-down module, it will bepossible to place the two outermost fixtures in a manner in which theyare displaced from each other, so that the line between the low pointsof these fixtures deviates from right-angles to the transport directionof the laying-down conveyor. With this embodiment, the changing of thisangle can take place only by constructional intervention, which hardlysatisfies the demands concerning flexibility which are placed inconnection with the primal cutting-up of meat items, namely in thecarrying out of optimised industrial primal cutting up.

The subsequent sub-claims 2-7 disclose how said demands for flexibilitycan be increased.

Claim 2 thus discloses adjustment means for fine adjustment of thefixtures by relative horizontal displacement along with the spacingbetween the belt of the laying-down conveyor. In practice, thispossibility of fine adjustment will be sufficient in connection with thecarrying out of optimised industrial cuts, where most often there is aneed only to achieve smaller relative displacements between the lowpoints of the two outermost fixtures in order for the line between theseto form an angle which deviates from right-angles to the transportdirection of the laying-down conveyor.

On the other hand, if a subsequent ham cut (“Belgian cut”) is to bemade, it will be necessary to place the fixtures, possibly with theadjustment means disclosed in claim 2, on the angling-out mechanismdisclosed in claim 3, whereby the laying-down fixtures are relativelydisplaced by an actual movement each time a meat item is received fromthe suspension conveyor, so that the low points of the two outermostfixtures are lying on a line which forms a predetermined angle inrelation to the transport direction, so that the carcasses in thisposition are placed on the laying-down conveyor at an inclined angle,and in this position are transported further by the laying-down conveyorto subsequent steps in the process.

Furthermore, as disclosed in claim 4, the adjustment means can beprovided with actuators, so that during operation of the laying-downmodule, adjustments of the angling-out of the meat items can be carriedout before these are laid down on the laying-down conveyor for furthertransport to subsequent steps in the process.

It will be obvious that the laying-down module will be able to bearranged for receiving half carcasses for primal cutting-up which aretransported successively in pairs on the suspension conveyor. Alaying-down module arranged for this purpose is disclosed in claim 5,where the related carcasses are angled-out in a laterally reversedmanner, but with the same degree of angling-out.

With the view to achieving a further optimisation of the subsequentprimal parting process, it can also be advantageous to be able to carryout an adjustment of the angling-out in relation to a fix-pointdetermination such as disclosed in claim 6.

With the view to achieving a well-defined and uniform positioning of thelengthways axes of the half carcasses when these are received, theU-shaped hoop fixtures can be configured as disclosed in claim 7. It ishereby achieved that the half carcasses which are thrown off from theconveyor slide down in the correct position for angle positioning.

A system for the primal parting of meat items, i.e. half carcasses ofpigs, and comprising a laying-down module, a vision detection system forthe determination of relevant fix points on meat items, a calculationunit with interface for the controlling of a positioning module, and asaw module, is disclosed in claim 8, and can be provided with alaying-down module disclosed in any of the claims 1-7, and which alsohas the characteristics disclosed in points b and c in claim 8.

The advantages of the system according to claim 8 should be obvious,i.e. providing this includes a laying-down module with all of thecharacteristics disclosed in claims 1-7, in that there is herebyachieved a fully-automatic system for primal parting of meat items,which practically speaking enables automatically-implemented parting ofmeat items in accordance with any desired cut positioning, and whichalso allows continuous optimisation of the cut positioning, not only inrelation to average considerations concerning the determination of fixpoints on a series of transported meat items/carcasses, but optimisationin relation to fix-point determinations carried out on each individualmeat item, and subsequent placing of the ideal cut line on the basis ofempirical ideal cut lines for a meat item with size and fix-pointplacing determined by the vision detection system.

A more simple system for primal parting of the disclosed kind can,however, be arranged as disclosed in claim 9.

In claim 10 there is disclosed a method based on a vision detectionsystem for primal parting of meat items, i.e. half carcasses of pigs.The method according to the invention is based on the use of theabove-mentioned known vision system for detection of the fix pointswhich form the basis for the positioning of the parting cuts, no matterwhether these are standard industrial cuts or ham cuts (“Belgian cuts”),or other special cuts such as optimised industrial cuts used in theprimal cutting-up, so that manual handling in the cutting-up process isavoided, and also so that human errors in connection with the placing ofthe cuts are eliminated. In this connection it should be mentioned thatthe angles V₁ and V₂ can assume the value zero (typically withindustrial parting cuts).

With the invention, use is thus made of the fact that the calculation ofthe positioning of the fix point in relation to the zero line can becarried out no matter whether the half carcasses arrive at thepicture-taking section with the lengthways direction arranged atright-angles to the transport direction, or at an angle which deviatesfrom right-angles.

Whether the half carcasses arrive at the picture-taking section withlengthways direction at right-angles to the direction of transport, orat an angle which deviates from this, is thus determined on the basis ofhow the primal cutting-up of the half carcasses is to be carried out bythe saw module, the blades of which are oriented parallel with thetransport direction. If, for example, a traditional industrial cut is tobe effected, where the half carcass is divided with a fore-end cutand/or a rear-end cut, it is normally preferred that the half carcass isconveyed into the cutting plant (and herewith to the picture-takingsection) with the lengthways direction arranged at right-angles to thetransport direction, after which said cut is effected in relation to thepubis and especially the armpit, typically so that upon passage of thepositioning module, the half carcass is positioned in relation to thecutting line of the ham saw, with starting point in the positioning ofthe pubis, and the cut line of the saw system's fore-end saw is lined upin relation to the position of the armpit.

If a “Belgian cut” (ham cut) is to be effected, it is preferred that thehalf carcass be conveyed into the cutting plant (and herewith to thepicture-taking section) with lengthways direction oriented at aninclined angle in relation to the transport direction, after which thecut is effected solely in relation to the position of the pubis, whichis made possible by the laying-down module according to the invention.

With the combination between the use of a vision-controlled positioningand cutting-up system and the laying-down module according to theinvention, with the invention there is achieved a fully-automatic andvery precise cutting-up of half carcasses which shall be parted withBelgian cuts (ham cuts) and optimised industrial cuts, in that the halfcarcasses are laid down on the laying-down conveyor with the lengthwaysdirection of the carcass at a pre-selected angle in relation to thetransport direction, corresponding to the preferred angle with which thecutting-up with Belgian cuts, or optimised industrial cuts, is carriedout with a cutting system which has saw blades arranged parallel withthe transport direction.

In the following, the invention is explained in more detail withreference to the drawing, where

FIG. 1 is a schematic plan view of a fully-automatic vision-controlledcutting-up system with laying-down modules according to the invention,and comprising an angle-positioning system,

FIG. 2 is a detail view of the procedure of laying-down half carcassesin the laying-down module,

FIGS. 3a and 3 b are detail side views of the laying-down moduleaccording to the invention,

FIG. 4 is a plan view of FIG. 5 showing the angling-out mechanism,

FIG. 5 is a schematic plan view of the system shown in FIG. 1 in thecarrying out of Belgian cuts, and

FIG. 6 is the same as FIG. 5, but where industrial cuts are carried out.

FIG. 1 shows a schematic view of an embodiment of a fully-automaticcutting-up system for primal parting of half carcasses of pigs. Thesystem is intended for adjustment for carrying out practically all typesof known, desired primal parting cuts.

In the embodiment shown, the cutting-up system comprises a laying-downmodule 2, a vision system 4 (with associated calculation unit andinterface for actuators which are not shown in detail, in that this isconsidered to be known technique), placed over a positioning module 6,and a saw module 8. Above the laying-down module 2, there extends alaying-down conveyor 10 (cf. FIG. 2) for the successive delivery ofrelated half carcasses 12 to the laying-down module 2.

As indicated in FIG. 1, and as shown clearly in FIGS. 2, 3A, 3B and 4,the laying-down module 2 comprises a set of substantially U-shapedlaying-down fixtures 14 which are laterally reversed in relation to eachother. As will appear from FIGS. 3A and 3B, the fixtures 14 aresuspended on a vertically-displaceable base frame 16 between two outerpositions, where the upper sides of the fixtures are lying at a levelabove the laying-down module's conveyor 18, and respectively where theuppermost parts of the fixtures 14 are lying at a level below thesurface of the conveyor belt.

As will appear from FIG. 1, the conveyor 18 is divided into fourtracks/belts 20, 22, 24, 26, which are mutually spaced apart by thespaces 21, 23, 25. The breadth of the tracks/belts is determinedrespectively by a preferred total belt breadth of the conveyor 18, andby the distance between the individual hoops in the fixtures 14. Theindividual belts are moved in a synchronous manner in the transportdirection of the conveyor. The transport direction of the conveyor andthe transport direction of the whole of the cutting-up system isindicated by the arrow 28 in FIG. 1.

The fixtures 14 are also connected to an angling-out mechanism 30 cf.FIG. 4 mounted on a base frame 16. The angling-out mechanism isconnected with the fixtures 14 via rod connections 32 with pivot link34, which in turn stand in connection with an actuator in the form of adisplaceable piston 36, the displacement of which causes a mutuallyreversed displacement in the lateral direction of the anchoring pointsfor the U-shaped fixtures, so that the line 40 which is described by thelow points 38 of the U-shaped fixtures 14 is displaced from a directionat right-angles to the transport direction 28 of the conveyor, so thatthis line forms an angle V₁ or V₂ which deviates from right-angles. Theangling-out mechanism also comprises adjustment mechanisms 42 for fineadjustment of the angular displacement.

It should be noted that the angling-out mechanism 30 can be completelyomitted, providing that the system is intended for use only for thecarrying out of industrial parting cuts or optimised industrial cuts,where the meat items /carcasses 12 are laid down on the conveyor 18 in aposition where the low points 38 of the outermost U-shaped hoops in thelaying-down fixtures 14 are lying on a line at right-angles to thetransport direction 28 of the conveyor, possibly with a small angulardeviation adjusted by means of the adjustment mechanism 42 , forcarrying out an optimised industrial cut. If it is desired to effectindustrial parting cuts only, the adjustment mechanism 42 can also beomitted.

In FIG. 2 it is shown how the half carcasses 12 are laid down on thelaying-down module 2 from a laying-down conveyor 10. The half carcasses12 are laid down on the raised fixtures 14 which are disposed in thereceiving position above the belts 20, 22, 24, 26 of the conveyor. Thehalf carcasses 12 are hooked off the conveyor 10, which is determined bythe length of the half carcasses. Moreover, the half carcasses aretransported in pairs to and subsequently laid down in the fixtures 14.

The positioning module 6 comprises two conveyors 44, 46 placed inextension of each other, where above the conveyor 44 closest to thelaying-down module 2 there is placed a vision camera 4. By means of aknown technique, the conveyors 44, 46 are displaceable in the sidewaysdirection by not-shown actuators, as indicated by the arrows 48, 50. Theactuators for the sideways displacement of the conveyors 44, 46 arecontrolled by a computer (not shown).

The saw module 8 comprises a ham saw 52 and a side-ways-displaceablefore-end saw 54. The saw blades are oriented parallel with the transportdirection 28 in the cutting plant, and have an extent so that the edgesextend a distance down below the surface of the conveyor belt 56, 58 ofthe saw module.

The fully-automatic primal cutting-up system's laying-down module 2,positioning system 6, vision system 4 and saw module 8, are allconnected to a computer (not shown) which, on the basis of the visionsystem's picture analysis, calculates the actual positioning of the fixpoints for the positioning of the parting cuts for the desiredcutting-up, in relation to a zero line. Hereafter, the half carcasses 12are moved in by sideways displacement of the positioning conveyor'sbelts 44, 46, preferably so that the placing of the ham cut, which isdetermined by the position of the pubis, is positioned in relation tothe saw-blade line 60 for the ham saw 52, after which the fore-end sawis displaced in the sideways direction in relation to the desiredplacing of the fore-end parting cut, which is typically determined onthe basis of the position of the ulna. Hereafter, the half carcasses aretransferred through the saw module during the carrying out of theparting cuts.

In connection with fully-automatic parting with “Belgian cuts”, whichcomprises only a single inclined ham cut in between the groin of thecarcass and across the carcass towards the ham, it will be necessary touse the angling-out mechanism 30, so that the lengthways direction ofthe carcass is arranged at an angle V₂ in relation to the direction oftransport through the saw line 60 for the ham saw 52 of the saw module.

However, a certain angling-out of the half carcasses 12 is alsorequired, though less than the angling-out with the “Belgian cut”, whencarrying out a traditional industrial parting cut, which comprises twocuts, i.e. the ham cut and the fore-end cut along the saw lines 60, 62.The changeover for this purpose can quickly be carried out by means ofthe angle adjustment mechanism 42.

In FIG. 5A to 5H it is shown how the parting of half carcasses 12 withthe “Belgian cut” is carried out with a fully-automatic cutting system.In FIG. 5A, a first pair of half carcasses 12 arrive at the laying-downmodule 2 in the fixtures 14 (not shown for the sake of clarity), afterwhich an angling-out (FIG. 5B) is carried out by the angling-outmechanism 30 (FIG. 4) and a subsequent lowering of the fixtures 14 (cf.FIG. 3B). The first of the two half carcasses 12 is fed in the transportdirection 28 on to the positioning conveyor 44 (FIG. 5C), where thevision system 4 takes a picture of the half carcass, and this is sent toa picture analysis unit (not shown) which determines relevant fix pointson the carcass for the positioning of the parting cuts, after which(FIG. 5D) the half carcass 12 is transferred to the positioning conveyor46 where a positioning of the carcass 12 is carried out in relation tothe saw line 60 for the ham saw 52. At the same time, the second halfcarcass 12 is fed in under the vision system 4 for the taking of apicture. Hereafter, the foremost positioned half carcass 12 is fed (FIG.5E) forwards towards the saw module's saw 52, and the next pair of halfcarcasses 12′ are received in the laying-down module 2, and the sawingof the foremost half carcass is started (FIG. 5F) at the same time thatthe positioning of the second half carcass is effected by the sidewaysdisplaceable conveyor 46 in the positioning module 6, and the next pairof half carcasses 12′ are angled-out in the laying-down module 2. Afterpositioning of the second half carcass 12, this is fed into the sawmodule 8 (FIG. 5C) where sawing-up is commenced along the line 60. Atthe same time, the foremost half carcass 12′ of the next pair of halfcarcasses is fed to the vision system 4 on the conveyor 44 for thetaking of a picture. With the sawing of the rearmost half carcass 12(FIG. 5H) of the first pair of half carcasses 12, the foremost halfcarcass 12′ of the second pair of half carcasses 12′ is positioned bythe sideways displaceable conveyor 46 at the same time that the secondhalf carcass is photographed by the vision system on the conveyor 44.Hereafter, the procedures as described above are repeated.

FIGS. 6A-6G show fully-automatic cutting-up when carrying out atraditional industrial cut, without angle positioning at the laying-downmodule 2, but where in the same manner as described above there iscarried out a fix-point determination by the vision system 4 (FIG. 6B),a subsequent positioning in the sideways direction (FIG. 6C) for the cutline 60 for the ham saw 52, and a simultaneous positioning of thefore-end saw 54, followed by the feeding of the foremost half carcass 12to the saw module 8 (FIG. 6D, positioning of the second half carcass 12(FIG. 6E), and at the same time as the arrival of the next pair of halfcarcasses 12″ in the laying-down module 2. The only difference in theimplementation of the sequences for the industrial cut is that herethere is also carried out a positioning of the cut line 62 for thefore-end saw 54 on the basis of a further fix point determined by thevision system, and that as opposed to the implementation of the ham cut,use is made of the fore-end saw.

There is thus disclosed a fully-automatic primal cutting system forcarrying out “Belgian cuts” and ordinary industrial cuts, possiblyeffected in an angle-positioned implementation as a so-called optimisedindustrial cut.

In conclusion, it should be noted that the different configurations ofthe laying-down module 2, as disclosed in the claims, have the resultthat the fully-automatic primal cutting system according to theinvention comprising the laying-down module 2, can assume embodiments ina corresponding manner. All depending on desires and requirements withregard to the positioning and optimisation of the positioning of theparting cut, the primal cutting system can thus be arranged within thescope of the patent claims.

What is claimed is:
 1. Laying-down module for a system for primalcutting-up of meat items, comprising: a laying-down conveyor withspaced, synchronously-driven tracks, an angle-positioning moduleconnected to the laying-down conveyor, and at least one set ofsubstantially U-shaped laying-down fixtures in spaces between the tracksof the laying-down conveyor, lowest points on at least two outermost ofsaid fixtures lying on a line oriented substantially at right-angles toa transport direction of the laying-down conveyor, and said laying-downfixtures being housed on a base frame which is vertically displaceablebetween a first outer position where the laying-down fixtures arelocated above the laying-down conveyor and a second outer position wherethe laying-down fixtures are located below surfaces of the tracks of thelaying-down conveyor.
 2. Laying-down module according to claim 1,wherein the U-shaped laying-down fixtures are provided with adjustmentmeans for carrying out a relatively horizontal displacement of thesubstantially U-shaped laying-down fixtures in the spaces between thetracks of the laying-down conveyor, so that the line between the lowestpoints of the laying-down fixtures and the transport direction of thelaying-down conveyor forms an angle which can deviate from right-anglesrelative to the transport direction of the laying-down conveyor. 3.Laying-down module according to claim 2, wherein the base frame furthercomprises an angling-out mechanism driven by a drive mechanism, by meansof which the laying-down fixtures are horizontally displaceable betweenan angled-out position where lowest points of the laying-down fixturesare on a line at a right-angle to the transport direction of thelaying-down conveyor, and an angled-out position where said line formsanother, pre-selected angle in relation to the transport direction; andwherein the adjustment means is housed on the angling-out mechanism. 4.Laying-down module according to claim 3, wherein the adjustment meansare provided with actuators for automatic adjustment of the angle ofsaid line relative to the transport direction.
 5. Laying-down moduleaccording to claim 4, further comprising a suspension conveyor forsuccessively feeding meat items in pairs to the laying-down and anglepositioning module, wherein the angle-positioning module comprises twosets of substantially U-shaped laying-down fixtures in the spacesbetween the tracks of the laying-down conveyor, and where adjustment ofsaid angle by the adjustment means and the angled-out position by theangling-out mechanism, respectively, is such that the line between thelowest points of the laying-down fixtures and the transport direction ofthe laying-down conveyor forms an angle which can deviate fromright-angles relative to the transport direction of the laying-downconveyor in either of laterally reversed directions.
 6. Laying-downmodule according to claim 5, wherein the laying-down module is adaptedto perform a continuous adjustment of the angled-out position inaccordance with varying sizes of the conveyed meat items; wherein theactuators of the adjustment means and the angling-out mechanism,respectively, are connected to a computer control unit which receivesparameters concerning position of fixed points on the meat items from avision detection system, said computer control being provided withsoftware which is adapted to make adjustments based of optimisingcalculations for producing the most optimal cut.
 7. Laying-down moduleaccording to claim 1, wherein the U-shaped fixtures have a configurationsuch that they extend in an asymmetrical manner, sloping towards awell-defined low point.
 8. System for primal cutting-up of meat items,comprising a laying-down module, a vision detection system for thedetermination of relevant fix points on meat items, a calculation unitwith an interface for the controlling of a positioning module and a sawmodule, wherein: a) the laying-down module comprises a conveyor withplane tracks, b) the positioning module comprises at least one sidewaysdisplaceable conveyor, above which there is a vision camera which isconnected with a computer with vision detection software, which togetherconstitute a vision detection system for the determination of fix pointson the meat items, fed from the laying-down conveyor, in relation to azero line, and c) interface is provided between said computer andactuators for sideways displacement of at least one of the at least oneconveyor of the positioning module and saws in the saw module for theadjusting the relative position of the saws with respect to the fixpoints on the meat items.
 9. System according to claim 8, furthercomprising an angle-positioning module connected to the laying-downconveyor, and at least one set of substantially U-shaped laying-downfixtures in spaces between the tracks of the laying-down conveyor,lowest points of on at least two outermost of said fixtures lying on aline oriented substantially at right-angles to a transport direction ofthe laying-down conveyor, and said laying-down fixtures being housed ona base frame which is vertically displaceable between a first outerposition where the laying-down fixtures are located above thelaying-down conveyor and a second outer position where the laying-downfixtures are located below surfaces of the tracks of the laying-downconveyor.
 10. System according to claim 9, wherein the U-shapedlaying-down fixtures are provided with adjustment means for carrying outa relatively horizontal displacement of the substantially U-shapedlaying-down fixtures in the spaces between the tracks of the laying-downconveyor, so that the line between the lowest points of the laying-downfixtures and the transport direction of the laying-down conveyor formsan angle which can deviate from right-angles relative to the transportdirection of the laying-down conveyor.
 11. System according to claim 2,wherein the base frame further comprises an angling-out mechanism drivenby a drive mechanism, by means of which the laying-down fixtures arehorizontally displaceable between an angled-out position where lowestpoints of the laying-down fixtures are on a line at a right-angle to thetransport direction of the laying-down conveyor, and an angled-outposition where said line forms another, pre-selected angle in relationto the transport direction; and wherein the adjustment means is housedon the angling-out mechanism.
 12. Laying-down module according to claim11, wherein the adjustment means are provided with actuators forautomatic adjustment of the angle of said line relative to the transportdirection.
 13. System according to claim 12, further comprising asuspension conveyor for successively feeding meat items in pairs to thelaying-down and angle positioning module, wherein the angle-positioningmodule comprises two sets of substantially U-shaped laying-down fixturesin the spaces between the tracks of the laying-down conveyor, and whereadjustment of said angle by the adjustment means and the angled-outposition by the angling-out mechanism, respectively, is such that theline between the lowest points of the laying-down fixtures and thetransport direction of the laying-down conveyor forms an angle which candeviate from right-angles relative to the transport direction of thelaying-down conveyor in either of laterally reversed directions. 14.Laying-down module according to claim 13, wherein the laying-down moduleis adapted to perform a continuous adjustment of the angled-out positionin accordance with varying sizes of the conveyed meat items; wherein theactuators of the adjustment means and the angling-out mechanism,respectively, are connected to a computer control unit which receivesparameters concerning position of fixed points on the meat items from avision detection system, said computer control being provided withsoftware which is adapted to make adjustments based of optimisingcalculations for producing the most optimal cut.
 15. Laying-down moduleaccording to claim 9, wherein the U-shaped fixtures have a configurationsuch that they extend in an asymmetrical manner, sloping towards awell-defined low point.
 16. Method, based on a vision detection systemfor primal cutting-up of meat items comprising the following steps: a)the receiving of meat items fed successively onto a laying-down andangle positioning module by a suspension conveyor with lengthways axesof the meat items oriented substantially at right-angles to a transportdirection of a laying-down conveyor, b) the positioning of the meatitems at the laying-down and angle positioning module meat itemspositioned with the lengthways axes at a preferred angle in relation toa right-angle with respect to the transport direction of the laying-downconveyor, c) feeding the meat items on the laying-down conveyor in thetransport direction forward to a positioning module comprising at leastone sideways displaceable positioning conveyor, d) taking pictures ofthe meat items with the vision system brought to the positioningconveyor for the determination of fixed points thereon, e) positioningof the meat items at the positioning conveyor in relation to a zeroline, on the basis of the fixed points determined by the vision system,f) positioning of a saw in a saw module in relation to the positioningof the fixed points, g) feeding of the meat items to a conveyor at thesaw module, and h) the parting of the meat items by cutting-up with thesaw during transport of the meat items by the conveyor of the sawmodule.
 17. Method according to claim 16, wherein the meat items aretransported successively in pairs on the suspension conveyor to thelaying-down and angle positioning module, and wherein the taking ofpictures by the vision system for determination of the fixed points aretaken of at least a first of the two meat items of the pairs.
 18. Methodaccording to claim 16, wherein the meat items are half carcasses.